2-Methylene propane phosphonic acid esters

ABSTRACT

2-METHYLENE PROPANE PHOSPHONIC ACID ESTERS AND THEIR COPOLYMERS WITH ACRYLONITRILE ARE THE OBJECTS OF THE INVENTION. The fibres produced from the copolymers are flame-resistant and show increased thermal stability, improved affinity for dyes and fastness to light. The copolymers of acrylonitrile and 2methylene propane phosphonic acid esters - in addition to other comonomers - are produced by polymerizing the monomers in solution or - preferably - in an aqueous suspension or emulsion. Formed articles, such as fibres from said copolymers can be prepared by spinning a solution of the copolymer in an organic solvent p.i. in dimethyl formamide.

United States Patent [191 Velker et al.

Z-METHYLENE PROPANE PHOSPHONIC ACID ESTERS Inventors: Eugen Velker,

Dormagen-Hackenbroich; Francis Bentz, Cologne; Gunther Nischk, Dormagen, all of Germany Assignee: Bayer Aktiengesellschaft,

Leverkusen-Bayerwerk, Germany Filed: Dec. 1, 1972 Appl. No.: 311,413

Foreign Application Priority Data Dec. 3, 1971 Germany 2160019 Dec. 3, 1971 Germany 2160021 US. Cl. 260/932; 260/80.-71; 260/50l.2l;

260/502.4 R; 260/502.4 P; 260/956; 260/969 Int. Cl. C07F 9/40 Field of Search 260/932, 956, 969

[451 Dec. 9, 1975 [56] References Cited UNITED STATES PATENTS 2,827,475 3/1958 Coover 260/969 X 2,843,617 7/1958 Kaufman 260/969 X 3,062,792 11/1962 McConnell et a1. 260/932 X 3,808,237 4/1974 Kerst..... 260/932 X Primary ExaminerRichard L. Raymond Attorney, Agent, or Firm-Plumley & Tyner [57 ABSTRACT 2-methylene propane phosphonic acid esters and their copolymers with acrylonitrile are the objects of the invention. The fibres produced from the copolymers are flame-resistant and show increased thennal stability, improved affinity for dyes and fastness to light. The copolymers of acrylonitrile and Z-methylene propane phosphonic acid esters in addition to other comonomers are produced by polymerizing the monomers in solution or preferably in an aqueous suspension or emulsion. Formed articles, such as fibres from said copolymers can be prepared by spinning a solution of the copolymer in an organic solvent p.i. in dimethyl formamide.

4 Claims, No Drawings Z-METHYLENE PROPANE PHOSPHONIC ACID H ESTERS This invention relates to 2-methylene propane phos- H2C20 2 H01 phonic acid esters and to acrylnitrile coploymers which 5 CH OH contain 2-methylene propane phosphonic acid in copo- 2 lymerised form in addition to other comonomers such C5261 as (meth) acrylic acid esters, 2-methylene propane-1,3- dichloride, vinyl chloride, vinylidene chloride or mix- H204: 2 tures of these comonomers. CH C1 The invention also relates to a process for producing 2 the aforemehhohed p y f and to films, fibres Preparation of the diol is known in the art. 2-methyfilaments? moulhhgs Qbtamed therefrom lene-1,3-propane diol can readily be obtained, for ex- The lf the lhvehhoh are 2'methylehe Propane ample, by reacting together isobutylene, oxygen and Phosphomc acld esters of the formula acetic acid, followed by hydrolysis of the acetyl groups.

CH In the case of the monophosphonic acid, the dihalo- CH d 1 gen compound is initially introduced and thereafter the 2 triester of phosphorous acid is added dropwise at tem- 2O peratures of from I 10 to 160C. The reaction is preferably carried out in the absence of solvents. The molar wherin R represents halogen (Cl, Br, I) or the radical ratio of the dihalogen compound to the phosphite amounts to between 1 l and 3 l. The reaction is ii carried out at temperatures in the range of from I l0to P 3 200C, the alkyl halide formed during the reaction 6R where a trialkyl phosphite is used as reactant being 4 contintuously distilled off. In order to complete the reaction, the reaction temperature can be maintained and 2 the radical for another 3 to 4 hours following the dropwise addition. ll To prepare the bis-phosphonic acid, the starting compounds in a molar ratio of dihalide to phosphite of CR from 1:2 to 1:4 are heated together to temperatures of from 120to 220C. In this case, too, the corresponding where R; is hydrogen, NI-I an alkalimetal, a C -C alkyl halide is removed from the reaction mixture by y an y halogen aryl or alkylaryl radical and R distillation, opitonally with the assistance of an inert hydrogen, a C C -alkyl, an aryl, halogenaryl, or an gas such as N where trialkyl esters of phosphorous alkylaryl radical. acid are used as reactant.

l-Halogen-Z-methylene propane-3-phosp C a i The reaction is completed when no more halide is diesters or 2-methylenepropane-l,3-bis-phosphonic evolved. If the dihalide is reacted with triaryl phosacid tetra-esters are prepared by reacting 1,3-dihalo- 40 phites, the reaction product is worked up by convengen-2-methylene propane with triesters of phosphorou tional methods. On completion of the reaction, the acid at elevated temperature the reaction may be efmore readily volatile constituents are distilled off in a fected in an organic solvent. For example, the reaction water-jet vacuum both in the case of the monophostakes place in accordance'with the following scheme: phonic acid ester and in the case of the bis-phosphonic ca 01 0 C1 2 C C 2 2 H2: Noczfig 3 H2 c P (oc H C H Cl O1 0 I c 01 c -P-(OC H H2 2 2 5 2 H c=c 2 P(OG H H C=C v CH Cl 2 C H Cl The l,3-dihalogen-2-methylene propane used as acid ester. The reaction products can be recovered by starting material can readily be prepared f om 2- conventional methods, for example by distillation in a methylene-1,3-propane diol and, for exam l thionyl high vacuum. The yields amount to between and chloride (where the halogen is chlorine). This combased on the phosphite used. pound can also be obtained from the corresponding A further object of the invention are acrylonitrile diol and hydrogen chloride in an organic solvent, for copolymers which comprises 60 to 99.9 by weight of example in accordance with the following reaction: acrylonitrile, the balance being up to 39.9 by weight CH -R H C=c 2 1 CH -R in which R represents halogen Cl, Br, I or the radical and R the radical O -i-OR where R is hydrogen, NH an alkali metal, a linear or branched, substituted or unsubstituted C,C -alkyl, aryl, halogenor alkyl-substituted aryl and R hydrogen a linear or branched, substituted or unsubstituted C C,,-alkyl, aryl optionally substituted by halogen or alkyl, said acrylonitrile copolymers having K-value according to Fikentscher in the range of from 60 to 120. Acrylonitrile copolymers are prefered comprising 60 to 90 by weight of acrylonitrile, 5 to 35 by weight of an ethylenically unsaturated, with acrylonitrile copolymerisable comonomer and 5 to 35 by weight of a copolymerised 2-methylene propane phosphonic acid ester preferably the K-values are in the range of 70 to 105.

The copolymerisation of ethylenically unsaturated compounds such as acrylonitrile, (meth) acrylic acid esters, Z-methylene propane-l ,3-dichloride, vinyl chloride, vinylidene chloride or mixtures of these comonomers and 2-methylene propane-phosphonic acid derivatives can be carried out by polymerising the monomers in solution and also in dispersion or suspension. l-ehloro-2-methylene propane-3-phosphonic acid diethyl ester and/or Z-methylene propane-1,3-bis -phosphonic acid tetraethyl ester are preferably used as starting compounds for copolymerisation.

It was surprising that substances of the above general formula should lend themselves to polymerisation with unsaturated compounds to form polymers with such good K-values (Fikentscher, Cellulosechemie 13, 58, 1932) in such high yields particularly since homopolymerisation was not possible and because substances of this type had been expected to show a negative effect as regulators in copolymerisation reactions. It was also surprising that the copolymerisation reaction should lead to products that are highly soluble, for example, in dimethylformamide, in other words that polymerisation should not be accompanied by crosslinking although the phosphorus compounds used, corresponding to the above general formula, show a substituted methallyl structure which is known to have a 4 polymerisation is carried out in nitric acid, it is possible in the usual way to use, for example, acetyl acetonates and oxidising agents, such as ammonium peroxy disulphate, as polymerisation initiators. The total quantity of the initiator and, where a redox system is used, the quantitative ratio of the oxidising agent to thereducing agent and the concentration of the monomers in the polymerisation solution are selected in accordance O with the data frequently published in the literature.

Precipitation polymerisations can be carried out in diluents such as, for example, water, low aliphatic alcohols and benzenes. Preferably polymerisation is carried out in an aqueous suspension or emulsion. It is advantal5 geous in some cases to add emulsifiers or suspending agents. Where polymerisation is carried out in water, as is preferably the case, conventional redox systems such as, for example, persulphate/bisulphite, are used as initiators. The quantitative ratio of the oxidising agent to the reducing agent is from 12 1 to 1 l5 and preferably from 8 l to 1 12. The total quantity of initiator amounts to between 0.1 and 15% by weight, based on the total monomer content and preferably to between 1 and 10 by weight.

Polymerisation is carried out in the acid range, preferably at pH-values of from 1.5 to 5, and at temperatures of from 0to 90C and preferably from 20to 55C, over reaction times which can vary from 1 hour to several days. The ratio by weight of total monomer to diluent amounts to between 1 2 and 1 25, preferageneral tendency towards crosslinking in polymerisably to between 1 5 and l 15.

The copolymers according to the invention contain different quantities of each comonomer, copolymerisation being carried out with starting mixtures containing from 0.1 to 40% by weight of the compounds of the above general formula, namely the mono or bis-phosphonates either on their own or mixed with one another in any ratio. Accordingly, the proportion of ethylenically unsaturated compounds, such as acrylonitrile, (meth) acrylic acid esters, Z-methylene propane-1,3- dichloride, vinyl chloride, vinylidene chloride or mixtures of these comonomers, amounts to between and 99.9% by weight at the beginning of polymerisa- 'tion, this figure once again applying either to an individual substance or to a mixture of unsaturated compounds. In the ease of precipitation polymerisations, the copolymers are isolated by filtration, which is preceded in the case of some polymerisation reactions by precipitation of the polymer, for example by adding a saturated solution of a strong electrolyte, such as sodium choride, sodium sulphate, zine sulphate or calcium chloride. Alternatively, precipitation is carried out by adding a small quantity of an electrolyte to the monomer dispersion before the reaction is initiated.

In the case of solution polymerisations, the polymer is separated off in the conventional way, for example by stirring the polymer solution into a precipitant, such as water or of lower aliphatic alcohols, followed by filtration. The yields amount to between 60 and 98 by weight, based on the total monomer content, whilst the K-value amount to between 60 and A further object of the invention are fibers and films of the acrylonitrile Z-methylene propane phosphonic acid copolymers and of mixtures thereof with other polymers. Fibres and films can be prepared by spinning or cashing a solution of the copolymer in an organic solvent p.i. dimethyl formamide.

The articles produced from the copolymers according to the invention are flame-resistant, i.e. substantially non-inflammable, they show increased thermal stability, improved affinity for dyes and fastness to light and, in some cases, they exhibit better pilling behavmm.

The LOl-values (limited oxygen index) quoted in the following Examples were determined by the so-called oxygen burning test. The apparatus used to carry out the oxygen burning test consists of a burning tube having a laterally attached nozzle through which an oxygen/nitrogen gas mixture flows and about one third of which is filled with glass beads in order to improve admixture of the gases. Fine-regulating valves accurately regulate the oxygen and nitrogen which flow through gas-flow meters. The oxygen andnitrogen are taken from the gas cylinders with pressure-reducing valves which are provided for this purpose. A needle frame is used as the specimen holder.

After the specimen holder has been set up with the specimen depending into the burning tube, the specimen is exposed from above to a gas flame. The mixing ratio of oxygen to nitrogen is varied until the specimens burns uniformly downwards with a minimum flame. The burning value n is calculated as follows:

n litres of O /h /(1itres of O /h +litres of. N /h) Test specimens:

Webs produced from fibres obtained by conventional spinning methods.

Dimensions of the test specimens:

Length 11 cm Width 9.5 cm 30 Before testing, all the materials to be tested are laid out for 24 hours in air at C/65% relative humidity.

The following examples illustrate more particularly the invention.

EXAMPLE 1 351 parts by weight of acrylonitrile, 29 parts by weight of methyl acrylate and 20 parts by weight of l-chloro-Z-methylene propane-3-phosphonic acid diethyl ester are taken up in 5,000 parts by volume of water. The pH-value is adjusted to 3.0 with dilute acid and polymerisation is initiated at 50C. by the addition with stirring of 3 parts by weight of potassium persulphate and 5 parts by weight of sodium metabisulphite to the reaction mixture while nitrogen is passed through. After 7 hours, the polymer is filtered off under suction, washed with water and methanol and dried in vacuo at C until constant in weight. Yield: 380 parts by weight (95%), K-value: 78.

The polymer is spun into fibres which are subse- 50 quently processed to form a web with the dimensions specified above. LOI-value n 0.212.

COMPARISON EXAMPLE 1 A copolymer of 93.8% by weight of acrylonitrile, 5.5% by, weight of methyl acrylate and 0.7 by weight of sodium methallyl sulphonate with a K-value of 83.8 is spun into fibres which are subsequently processed into a web. LOT-value: n 0.200.

EXAMPLE 2 K-value: 90

reaction mixture while nitrogen is continuously passed through. After 3.5 hours, a further 1.5 parts by weight of potassium persulphate and 3.5 parts by weight of sodium metabisulphite are added. The total polymerisation time amounts to 7 hours. The polymer is then filtered off under suction, washed with water and methanol and dried in vacuo at 50C until constant in .weight. Yield: 355 parts by weight (88.7%), K-value: 86.5

LOl-value (web): n 0.250

LOI-value (comparison example 1): n 0.200.

EXAMPLE 3 The polymerisation of 265 parts by weight of acrylonitrile, 20 parts by weight of methyl acrylate and 15 parts by weight of 2-methylene propane-1,3-bis-phosphonic acid tetra-ethyl ester in 4,000 parts by volume of water is initiated at 50C/pH-3.0 (dilute sulphuric acid) by the addition of 4 parts by weight of potassium persulphate and 4 parts by weight of sodium metabisulphite while nitrogen is continuously passed through. After 7 hours, the polymer is filtered off under suction, washed with water and methanol and dried in vacuo at 50C.

Yield: 250 parts by weight (83.4%)

K-value: 85.7

LOI-value (web): n 0.212

LOT-value (comparison example 1): n 0.200

EXAMPLE 4 260 parts by weight of acrylonitrile, 20 parts by weight of methyl acrylate and 31.1 parts by weight of Z-methylene propane-1,3-bis-phosphonic acid tetraethyl ester are polymerised in 4,000 parts by volume of water as in Example 3.

Yield: 288 parts by weight (74.4%), K-value: 84.3

EXAMPLE 5 260 parts by weight of acrylonitrile, 20 parts by weight of methyl acrylate and parts by weight of 2-methylene propane-1,3-bis-phosphonic acid tetraethyl ester are polymerised in 4000 parts by volume of water as in Example 3.

Yield: 215 parts by weight (61.5%), K-value: 86.4 LOI-value (web): n 0.287 LOT-value (comparison example 1): n 0.200

EXAMPLE 6 j 88 parts by weight of acrylonitrile, 7 parts by weight of methyl acrylate, 2.5 parts by weight of 1-chloro-3- methylene propane-3-phosphonic acid diethyl ester and 2.5 parts by weight of 2-methylene propane-1,3-

' bis-phosphonic acid tetra-ethyl ester are heated to 50C with stirring in 1,200 parts by volume of water while nitrogen is passed through. After the pH-value has been adjusted to 3.0 with dilute sulphuric acid, polymerisation is initiated by the addition of 1 part by weight of potassium persulphate and 1 part by weight of sodium metabisulphate. After 6 hours, the polymer is filtered off under suction, washed thoroughly, with water and methanol and dried in vacuo at 50C. Yield: 92.5 parts by weight (92.5%)

EXAMPLE 7 j 82 parts by weight of acrylonitrile, 7 parts by weight of methyl acrylate, 5 parts by weight of l-chloro-2- methylene propane-3-phosphonic acid diethyl ester and 5 parts by weight of Z-methylene propane-1,3-bisple 6.

Yield: 76 parts by weight (76%) K-value: 101.8.

EXAMPLE 8 EXAMPLE 9 A mixture of 60 parts by weight of acrylonitrile, 35 parts by weight of vinylidene chloride, parts by weight of 1-chloro-2-methylene propane-3-phosphonic acid diethyl ester and 12 parts by volume of a 25% aqueous solution of phenyl-(3-methyacrylamino)-phe-.

nyl disulphimide in 1200 parts by volume of water is adjusted to a pH value of 3 by addition of dilute sulphuric acid at 28C. After the air has been displaced by nitrogen, polymerisation is initiated by the addition of 2 parts by weight of potassium persulphate and 4 parts by weight of sodium metabisulphite. After 5 hours, the polymer is filtered off under suction and the polymer is processed as described above.

Yield: 73 parts by weight (73%) K-value: 87.1.

EXAMPLE The monomer mixture described in Example 9 is polymerised in 800 parts by volume of water under the same reaction conditions as in Example 9.

Yield: 95 parts by weight (95%) K-value: 80.7.

EXAMPLE 1 1 In a three-necked flask equipped with a stirring mechanism and reflux condenser and which has been flushed free from air with nitrogen, 60 parts by weight of acrylonitrile, 27 parts by weight of vinylidene chloride, 10 parts by weight of 1-chloro-2-methylene propane-3-phosphonic acid diethyl ester and 12 parts by volume of a 25% aqueous solution of phenyl-(3-methacrylamido)-phenyl disulphimide are mixed with 500 parts by volume of water and, after heating to 28C, adjusted to pH 3.0. Polymerisation is then initiated by the addition of 5.8 parts by weight of potassium persulphate and 1.7 parts by weight of sodium metabisulphite. The polymer is filtered off under suction after 5 hours and processed as described above.

Yield: 78 parts by weight (78%) K-value: 76.5.

EXAMPLE 12 504 parts by weight of acrylonitrile, 256 parts by weight of vinylidene chloride and 40 parts by weight of Z-methylene' propane-1,3-bis-phosphonic acid tetraethyl ester are taken up in 8,000 parts by volume of water, heated to 28C and polymerisation is initiated under a nitrogen atmosphere at pH 3.0 by the addition 8 of 7.2 parts by weight of sodium metabisulphite and 0.6 parts by weight of potassium persulphate. The resulting polymer is filtered off under suction after 5 hours and worked up as described above. Yield: 624 parts by weight (78%) K-value: 82.8 LOI-value (web): n 0.287 LOI-value (comparison example 1 n 0.200

EXAMPLE 13 504 parts by weight of acrylonitrile, 176 parts by weight of vinylidene chloride and parts by weight of 2-methylene propane-l,3-bis-phosphonic acid tetraethyl ester are polymerised in 8,000 parts by volume of water under the conditions described in Example 12. A further 3.6 parts by weight of sodium metabisulphite and 0.3 part by weight of potassium persulphate are added after the polymerisation has been in progress for 2.5 hours. The total polymerisation time amounts to 5 hours.

Yield: 510 parts by weight (64%) K-value: 81.1 4 LOI-value (web): 0.315 LOI-value (comparison example 1): n 0.200

The web of this Example was also compared with a web consisting of 60% by weight of acrylonitrile, 37 by weight of vinylidene chloride, 3 by weight of phenyl-(3-methyacrylamino) -phe nyl disulphimide (1(- value 80.6 LOI-value: n 0.275

EXAMPLE 14 85 parts by weight of acrylonitrile, 5 parts by weight of 2-methylene propane-1,3-dichloride and 10 parts by weight of 1-ch1oro-2-methylene propane-3-phosphonic acid diethyl ester are polymerised under nitrogen in 1000 parts by volume of water at a temperature of 50C and at a pH-value of 3.0 by the addition of 1 part by weight of potassium persulphate and 1 part by weight of soduim metabisulphite. The total polymerisation time amounts to 7 hours. After the polymer has been filtered off under suction, it is washed thoroughly with water and methanol and dried in vacuo at 50C. Yield: 76 parts by weight (76%) K-value: 78.6

EXAMPLE 15 Preparation Of The Phosphonic Acid Esters EXAMPLE A l-chloro-2-methylene propane-3-phosphonic acid diethylesterv 34 parts by weight of 2-methylene propane-1,3- dichloride are heated to C, after which 30 parts by weight of triethyl phosphite are added dropwise with stirring. Ethyl chloride distills off continuously during the dropwise addition. On completion of the dropwise addition, the reaction temperature is increased slowly to 180C. After 3 to 4 hours at 180C, the evolution of ethyl chloride is at an end and the reaction is over. The excess dihalide is distilled off in a water-jet vacuum. The resulting 1-chloro-2-methylene propane-3-phosphonic acid diethyl ester is distilled off in a high vacuum Yield: 30.7 parts by weight (75% 'of the theoretical, based on triethyl phosphite) b.p: 83 90C/0.05 Torr Analysis: C H clO P (226.6)

C H Cl P Calculated: 42.3% 7.1% 21.2% 13.7%

5.7% found: 42.4% 6.3% 21.5% 14.1% Analysis: C H C1O P (226.6)

C H Cl 0 P EXAMPLE B 2-methylene propane -l,3-bis-phosphonic acid tetraethyl ester 50 parts by weight of 2-methylene-l,3-propane dichloride and 140 parts by weight of triethyl phosphite are heated with stirring to 150C. The reaction temperature is slowly increased to 180C and the reaction mixture is maintained at this temperature until no more ethyl chloride can be collected in a following cold trap. Thereafter the more readily volatile constituents are distilled off in a water-jet vacuum. The reaction product is recovered by distillation in a high vacuum. Yield: 105 parts by weight (80% of the theoretical, based on triethyl phosphite) b.p.: 157 l59C/0.02 Torr N/ 1.4542

in which R represents halogen or the radical 2O 'P OR and R the radical O n v P where R, and R are C -C 4-alkyl.

2. 2-methylene propane phosphonic acid esters vas claimed in claim 1, wherein R represents chlorine 3. Z-methylene propane -l.3-bis-phosphonic acid tetra-ethyl ester.

4. l-chloro-2-methylene propane -3-phosphonic acid 7 diethyl ester.

UNITED STATES PATENT AND TRADEMARK OFFICE QER'HHQATE OF CORRECTION PATENTNO. 1 3 925 515 DATED December 9,1975

INVENTOMS) I Eugen Velker et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 9, the first table, under the Column Cl 5.7% in all instances should be on the same line and not below and shoul be --l5.7%-

Analysis in the second instance should be deleted as it has been listed twice.

Signed and Bealed the eighth Day 6? Junel976 [seam Arrest:

RUTH C. MASON C. MARSHALL DANN Anesting Offirer I Commissioner uj'f'alems and Trademarks 

1. 2-METHYLENE PROPANE PHOSPHONIC ACID ESTER CORRESPONDING TO THE GENERAL FORMULA
 2. 2-methylene propane phosphonic acid esters as claimed in claim 1, wherein R1 represents chlorine
 3. 2-methylene propane -1.3-bis-phosphonic acid tetra-ethyl ester.
 4. 1-chloro-2-methylene propane -3-phosphonic acid diethyl ester. 